Method of removing frizziness from modacrylic filaments and imparting curl thereto



United States Patent a Corp. of Delaware METHOD OF REMOVING FRIZZINESSFROM MODACRYLIC FILAMENTS AND IMPARTING CURL THERETO 13 Claims, NoDrawings US. Cl 132/5 Int. Cl A4lg 5/00 Field of Search 132/5, 7,

Primary Examiner- Robert Peshock Assistant Examiner- Gregory E. McNeillAttorney-Wilkinson, Mawhinney and Theibault ABSTRACT: The presentinvention relates to a method of straightening crimped, bent, kinked orotherwise non-straight modacrylic filaments used particularly in thesynthetic hair styling art in pieces known as wigs, wiglettes, chignonsand falls which is accomplished by immersing the stylable modacrylicfilament in a heated solution of non-aqueous liquid, by way of example,of glycol or in an aqueous solution of saturated salt solution (sodiumchloride) for 10-60 seconds at 160- 210F.

METHOD OF REMOVING FRIZZINESS FROM MODACRYLIC FILAMENTS AND IMPARTINGCURL THERETO The present invention relates to method of removingfrizziness from modacrylic filaments, particularly those filamentsdesignated as stylable filaments extending from the artificial hairpiecedescribed in my U. S. Letters Patent No. 3,139,093 granted June 30,1964, which is manufactured in accordance with the process of my U. S.Letters Patent No. 3,199,516 granted August 10, 1965. The stylablefilaments which extend from the base member of the artificial hairpieceand which are to be styled in various forms of hair-dos have presentedproblems of frizziness in the past. Frizz in a filament is a wave orcrimp on almost a macroscopic basis which imparts tactile roughness andpoor appearance. This is difficult to describe but the lack ofsmoothness results in a glazed" artificial appearance.

Frizziness of modacrylic filaments has been a problem for a long timeand can be caused during any one of several stages in the processing ofthe fiber and during manufacturing of the wig. During dyeing,particularly in a kettle, the fibers tend to contract, deform and to beshaped by their contact with adjacent fibers. These irregularities mustbe removed in order to have a smooth hair-like filament. Drying undertension can make the fiber smooth. On the other hand, the heat usedduring drying can also cause irregularities. A small amount of frizz canbe imparted during preparation of the sliver. If curling temperature istoo high or if the operator does not wind the hair on the roller tightlyenough, frizzing results.

I have found it very difficult to strike a happy medium betweenimparting sufficient curl strength so that the curl stays in duringwashing and at the same time keeping frizz to a minimum. For example, ifI increase the temperature during curling by 5 F. or increase the timeby 10 minutes (l95- 225F. for 45 75 minutes now being employed),increased frizziness results.

Dynel is a thermoplastic material which because of its largely amorphousnature has no clearly defined melting point. Instead it begins to softenas the temperature is increased and at the same time the fiber begins tocontract (shrinks). The rate of these processes are dependent on thetemperature, i.e., as the temperature is increased the tendency tosoften and shrink goes up rapidly. Of course, Dynel would not be apractical textile material if these processes occurred at roomtemperature, but actually they begin to happen, although very slowly,even at temperatures as low as 150F.

Thus, the heat somewhat softens the fiber and begins to make it contractslightly and if the fiber is put onto a roll or held in some other formduring the time of heating and then cooled while in this configuration,a fairly permanent shape will be imparted. On a molecular basis whatprobably happens is that the increase in temperature breaks some of theweak secondary forces between the long chain molecules so that they canslide past each other (or uncoil) and then when they cool down newsecondary forces form between the chain and the fiber stays in this newcondition. Until it is heated again to a temperature at least as high asthat which was originally used to set the fiber, it will maintain itsnew conformation. Severe mechanical manipulation causes changes in thefiber by actual fracturing of sections, etc., which can cause the fiberto lose some of its set.

The heat that is applied can be in the form of dry heat or steam heat orthe fiber can actually be immersed in hot liquids. Indeed, some curlingcan be obtained by immersing the fiber in hot water but when oneimmerses modacrylic fibers in hot water another reaction begins to takeplace which commences above about 170F. At this point, the fiber beginsto swell and vacuoles" or microscopic voids filled with water areformed. When this fiber is removed from the hot water and air-dried,these vacuoles do not collapse and instead a fiber which is full oflittle tiny air spaces which act as a delusterant results.

The tendency to deluster in water above about 170F. is a problem whendyeing Dynel and Union Carbide carefully recommends drying it attemperatures above 250F. in order to reluster the fiber, oralternatively, suggests dyeing methods below 180F. which results in onlya small loss in luster.

In my work to remove frizz I observed that immersion of frizzy fibers insaturated salt solutions at elevated temperatures resulted in aspontaneous (without any external force applied) disappearance of frizzat temperatures in the range of 160 F., depending on the history of thespecific dye lot. This procedure was found adaptable for use on fabricfrom which wigs are made or on the wigs themselves. However, since hightemperatures are in themselves capable of setting a configuration, Ifound it necessary to brush the fabric and to orient the fibers into astraightened condition (on a macroscopic basis) before immersion intothe hot saline. Also in order to keep the fibers straight it was helpfulto brush the filaments while still warm, on their removal from the hotsaline.

Similar results were obtained with hot non-aqueous liquids with theadditional advantage that if the viscosity of the liquid is relativelyhigh the fibers maintain their aligned and straightened orientation sothat it is only necessary to brush before immersion.

We have explored the broad application of this principle which involvesthe use of liquids which do not swell Dynel. For the purpose ofprocessing efficiency and cost it is desirable to use materials whichare relatively inexpensive and which are easily washed off the filamentswith water. Of the non-aqueous materials evaluation we have found theglycols to be mostsatisfactory. For example, Union Carbides productsUcon l-llSN or H2N which are complex glycols are satisfactory for plantproduction. Ethylene glycol is satisfactory except that in some casesthere results some bleeding of dyes.

All the frizz, bends, crimp, etc., when removed somehow relaxed" thefiber so that in the subsequent curling operation there is little or notendency to frizz when the curl was being set either with dry heat or byimmersion in heated liquids.

I am not exactly sure of the mechanism of this pre-finishing orpre-conditioning treatment and why it then permits us to get betterresults. The fiber does not contract during this operation, in fact,some measurements made on individual fibers indicate that if anything,it elongates very slightly (1- 2%). Furthermore, individual fiber workhas shown that there is a very critical temperature at which thishappens and this varies slightly from lot to lot, probably depending onthe temperature used during dyeing, etc.

The spontaneous disappearance of frizz and the removal of the majorbends give a very smooth fiber. Having this good base to work with andthen curling properly achieves better results than I have ever had andwhat is most important less frizzing results during subsequent settingof the curl with heat. Perhaps the relatively simple explanation thatthe fiber is much straighter during actual curling so that it can bewound on the roller tighter is the most important factor.

Another important use for this technique of imparting curl with heatedliquid is for localized curling. For example, in chignons or falls inwhich the Dynel fibers are about 16 inches long but only about 4 inchesis desired to be curled at the end. I wrap the 4 inch end around metalrollers and then immerse the rollers into the heated liquid but I do notimmerse the hair above the rollers. lf dry heat is used and the wholefall is put into the oven, that portion above the 4 inch wrapped aroundthe roller gets frizzy.

While the word modacrylic filament is used in the claims, it will beunderstood that this may be a single filament, a tow length of filamentsor a fabric into which the filaments have been knit and extend from oneside thereof for subsequent styling.

While the term brushing the filaments is employed in the claims, it willbe appreciated that either brushing or combing are equivalents as longas it is a vigorous lineal action which tends to straighten thefilament.

Although I have disclosed herein the best forms of the invention knownto me at this time, I reserve the right to all such modifications andchanges as may come within the scope of the following claims.

lclaim:

1. The method of removing frizz from modacrylic filaments employed inarticles such as wigs, fabrics, wigletts and other hairpieces to imparta straight natural hair-like appearance comprising:

(a) immersing the article in a non-aqueous glycol liquid at an elevatedtemperature for a short time period.

(b) removing the article from the liquid and allowing it to cool, and

(c) rinsing the article to remove the liquid.

2. The method of Claim 1 wherein the temperature of the glycol is of theorder of 200F.

3. The method as claimed in Claim 2 wherein the period of immersion isof the order of 15 seconds.

4. The method of removing frizz from modacrylic filaments employed inarticles such as wigs, fabrics, wigletts and other hairpieces to imparta straight natural hair-like appearance comprising:

(a) immersing the article in a saturated solution of a salt of the groupof sodium chloride, sodium sulfate, at an elevated temperature for ashort time period.

(b) removing the article from the liquid and allowing it to cool,and

(c) rinsing the article to remove the liquid.

5. The method of Claim 4 wherein the temperature of the liquid is ofarange of the order of 160 210F.

6. The method of Claim 5 wherein the immersion is in multiple steps ofseconds duration each.

7. The method of straightening modacrylic filaments employed in articlessuch as wigs, fabrics, wiglettes and other hairpieces to remove frizzand to impart a straight natural hair-like appearance comprising:

(a) immersing the article in a glycol at a temperature of the order of200F. for a period of 10-60 seconds,

(b) hanging the article and permitting the heated glycol to run off bygravity drain, and

(c) washing the article to remove the glycol.

8. The method of imparting curl to modacrylic filaments employed inarticles such as wigs, fabrics, wigletts and other hairpiecescomprising:

(a) arranging the filaments into curls or rolls,

(b) immersing the curled and rolled article into a nonaqueous glycolliquid at an elevated temperature for a short time period,

(c) removing the article from the liquid and allowing it to cool, and

(d) rinsing the article to remove the liquid.

9. The method of Claim 8, wherein the temperature of the glycol is ofthe order of 200 degrees Fahrenheit.

10. The method of Claim 9, wherein the period of immersion is of theorder of fifteen seconds.

11. The method of imparting curl to modacrylic filaments employed inarticles such as wigs, fabrics, wigletts and other hairpiecescomprising:

(a) arranging the filaments into curls or rolls,

(b) immersing the curled and rolled article into a saturated solution ofsalt of the group of sodium chloride and sodium sulfate at an elevatedtemperature for a short time period,

(c) removing the article from the liquid and allowing it to cool, and

(d) rinsing the article to remove the liquid.

12. The method of Claim 11, wherein the temperature of the liquid is ofa range of the order of degrees to 210 degrees Fahrenheit.

13. The method of Claim 12, wherein the immersion is in a time period ofthe range of fifteen to sixty seconds.

